Prepare for the UCF Biological Principles Exam. Use flashcards and multiple-choice questions with hints and explanations to succeed on your exam!

A heart attack, medically known as a myocardial infarction, primarily occurs due to the blockage of coronary arteries. These arteries supply blood to the heart muscle itself. When these arteries become narrowed or blocked, often due to the build-up of plaque (a mix of fat, cholesterol, and other substances), the blood flow to a part of the heart muscle is reduced or cut off entirely. Without sufficient blood flow, the affected heart muscle begins to die, which leads to the symptoms and complications associated with a heart attack.

In contrast, other options relate to different aspects of cardiovascular or overall health. For example, a blockage of brain arteries refers to a stroke, not a heart attack, and excessive blood flow to the heart is not a condition that leads to a heart attack; rather, it can occur during other physiological conditions or exercise. A heart muscle infection, while a serious condition, leads to a different category of cardiac issues, such as myocarditis, and is not a direct cause of a heart attack. Understanding how coronary artery blockage correlates with decreased blood flow emphasizes its critical role in the occurrence of heart attacks.